I am a faculty member in the Department of Computer Science and Cognitive Science Program at the University of Toronto. My research explores the interplay of language, cognition and computation with a focus on understanding the human lexicon.
Natural language relies on a finite vocabulary to express an unbounded array of ideas. I study how language evolves and develops to convey emerging meanings and the extent to which the underlying cognitive foundations may be specified computationally. For some time, I have been interested in the problems of semantic change and word meaning extension and developing models of cognitive mechanisms (e.g. chaining, metaphorization) and semantic knowledge associated with these processes.
In a related line of work, I investigate cross-language variation through the lens of communicative efficiency. I also develop language-based tools for exploring cognitive domains such as morality.
Language evolution and development
- Yu, L. and Xu, Y. (2025) Infinite mixture chaining: An efficiency-based framework for the dynamic construction of word meaning. Open Mind, 9: 1–24.
- Ramezani, A., Stellar, J.E., Feinberg, M., and Xu, Y. (2024) Evolution of the moral lexicon. Open Mind, 8, 1153-1169.
- Brochhagen, T., Boleda, G., Gualdoni, E., and Xu, Y. (2023) From language development to language evolution: A unified view of human lexical creativity. Science, 381(6656), 431-436.
- Hahn, M. and Xu, Y. (2022) Crosslinguistic word order variation reflects evolutionary pressures of dependency and information locality. PNAS, 119(24), e2122604119.
- Xu, A., Stellar, J.E., and Xu, Y. (2021) Evolution of emotion semantics. Cognition, 217, 104875.
- Ferreira Pinto Jr., R. and Xu, Y. (2021) A computational theory of child overextension. Cognition, 206, 104472.
- Habibi, A.A., Kemp, C., and Xu, Y. (2020) Chaining and the growth of linguistic categories. Cognition, 202, 104323.
- Ramiro, C., Srinivasan, M., Malt, B.C., and Xu, Y. (2018) Algorithms in the historical emergence of word senses. PNAS, 115(10), 2323-2328.
- Xu, Y., Malt, B.C. and Srinivasan, M. (2017) Evolution of word meanings through metaphorical mapping: Systematicity over the past millennium. Cognitive Psychology, 96, 41-53.
Cross-language variation
- Xu, A., Kemp, C., Frermann, L., and Xu, Y. (2024) Word reuse and combination support efficient communication of emerging concepts. PNAS, 121(46), e2406971121.
- Xu, Y., Duong, K., Malt, B.C., Jiang, S., and Srinivasan, M. (2020) Conceptual relations predict colexification across languages. Cognition, 201, 104280.
- Xu, Y., Liu, E., and Regier, T. (2020) Numeral systems across languages support efficient communication: From approximate numerosity to recursion. Open Mind, 4, 57-70.
- Kemp, C., Xu, Y., and Regier, T. (2018) Semantic typology and efficient communication. Annual Review of Linguistics, 4:109-128.
- Xu, Y., Regier, T. and Malt, B.C. (2016) Historical semantic chaining and efficient communication: The case of container names. Cognitive Science, 40(8):2081-2094.
- Ramezani, A. and Xu, Y. (2025) Moral association graph: A cognitive model for automated moral inference. Topics in Cognitive Science, 17, 120-138.
- Ramezani, A. and Xu, Y. (2023) Knowledge of cultural moral norms in large language models. In ACL.
- Prystawski, B., Grant, E., Nematzadeh, A., Lee, S.W.S., Stevenson, S., and Xu, Y. (2022) The emergence of gender associations in child language development. Cognitive Science, 46, e13146.
- Sun, Z., Zemel, R., and Xu, Y. (2021) A computational framework for slang generation. TACL, 9, 462-478.
- Xie, J.Y., Ferreira Pinto Jr., R., Hirst, G., and Xu, Y. (2019) Text-based inference of moral sentiment change. In EMNLP-IJCNLP, 4654-4663, Hong Kong, China.
